<nz-collapse>
    <nz-collapse-panel *ngFor="let w of borders; let f = first" [nzActive]="f" [nzHeader]="w.name">
        <div (dragstart)="onDragStart($event, c)" *ngFor="let c of w.borders" class="component" draggable="true">
            <img [alt]="c.name" [src]="c.url" [title]="c.name || c.url" loading="lazy"/>
        </div>
    </nz-collapse-panel>
</nz-collapse>
<nz-empty *ngIf="!borders" nzNotFoundContent="相册为空"></nz-empty>
